Alright, let's solve this math problem step by step. First, we have the number 85. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 81. So, we're going to take the number 85 and add it to itself 81 times.
Step 1: 0 + 85 = 85
Step 2: 85 + 85 = 170
Step 3: 170 + 85 = 255
Step 4: 255 + 85 = 340
Step 5: 340 + 85 = 425
Step 6: 425 + 85 = 510
Step 7: 510 + 85 = 595
Step 8: 595 + 85 = 680
Step 9: 680 + 85 = 765
Step 10: 765 + 85 = 850
Step 11: 850 + 85 = 935
Step 12: 935 + 85 = 1020
Step 13: 1020 + 85 = 1105
Step 14: 1105 + 85 = 1190
Step 15: 1190 + 85 = 1275
Step 16: 1275 + 85 = 1360
Step 17: 1360 + 85 = 1445
Step 18: 1445 + 85 = 1530
Step 19: 1530 + 85 = 1615
Step 20: 1615 + 85 = 1700
Step 21: 1700 + 85 = 1785
Step 22: 1785 + 85 = 1870
Step 23: 1870 + 85 = 1955
Step 24: 1955 + 85 = 2040
Step 25: 2040 + 85 = 2125
Step 26: 2125 + 85 = 2210
Step 27: 2210 + 85 = 2295
Step 28: 2295 + 85 = 2380
Step 29: 2380 + 85 = 2465
Step 30: 2465 + 85 = 2550
Step 31: 2550 + 85 = 2635
Step 32: 2635 + 85 = 2720
Step 33: 2720 + 85 = 2805
Step 34: 2805 + 85 = 2890
Step 35: 2890 + 85 = 2975
Step 36: 2975 + 85 = 3060
Step 37: 3060 + 85 = 3145
Step 38: 3145 + 85 = 3230
Step 39: 3230 + 85 = 3315
Step 40: 3315 + 85 = 3400
Step 41: 3400 + 85 = 3485
Step 42: 3485 + 85 = 3570
Step 43: 3570 + 85 = 3655
Step 44: 3655 + 85 = 3740
Step 45: 3740 + 85 = 3825
Step 46: 3825 + 85 = 3910
Step 47: 3910 + 85 = 3995
Step 48: 3995 + 85 = 4080
Step 49: 4080 + 85 = 4165
Step 50: 4165 + 85 = 4250
Step 51: 4250 + 85 = 4335
Step 52: 4335 + 85 = 4420
Step 53: 4420 + 85 = 4505
Step 54: 4505 + 85 = 4590
Step 55: 4590 + 85 = 4675
Step 56: 4675 + 85 = 4760
Step 57: 4760 + 85 = 4845
Step 58: 4845 + 85 = 4930
Step 59: 4930 + 85 = 5015
Step 60: 5015 + 85 = 5100
Step 61: 5100 + 85 = 5185
Step 62: 5185 + 85 = 5270
Step 63: 5270 + 85 = 5355
Step 64: 5355 + 85 = 5440
Step 65: 5440 + 85 = 5525
Step 66: 5525 + 85 = 5610
Step 67: 5610 + 85 = 5695
Step 68: 5695 + 85 = 5780
Step 69: 5780 + 85 = 5865
Step 70: 5865 + 85 = 5950
Step 71: 5950 + 85 = 6035
Step 72: 6035 + 85 = 6120
Step 73: 6120 + 85 = 6205
Step 74: 6205 + 85 = 6290
Step 75: 6290 + 85 = 6375
Step 76: 6375 + 85 = 6460
Step 77: 6460 + 85 = 6545
Step 78: 6545 + 85 = 6630
Step 79: 6630 + 85 = 6715
Step 80: 6715 + 85 = 6800
Step 81: 6800 + 85 = 6885

So, 85*81 = 6885